1. Field of the Invention
The invention relates to the formation of concrete pipe; and more particularly, to apparatus and method for forming continuous and seamless concrete pipe in situ in a ditch or the like.
2. Description of the Prior Art
It has been suggested that concrete pipe be formed in situ in ditches or the like using machines such as those described in U.S. Pat. Nos. 3,534,449 and 2,731,698. Although the pipes formed by such machines are satisfactory from a structural strength point of view, such pipes are produced using forms or the like which are removed after formation of the pipe and prior to utilization thereof. Such forms are necessary in order to form a pipe which is generally cylindrical and wherein the top half is as strong as the bottom half. Further, since the forms must be removed so that they do not impede the subsequent flow of fluids or the like through the completed pipes, time and labor are involved both in their placement and in their removal. Also, the area of the pipe at the lower edges of the forms are left rough which, although not pertinent from a structural point of view, results in a pipe having an interior not completely smooth and thus tending to affect the flow characteristics of the pipe.